KSEF RDE: Nanoelectronics of Two-and Three- Terminal Junctions of Graphene Ribbons

The recent discovery of free state graphene has generated tremendous interest in the scientific community [1] following the isolation of individual freely suspended graphene sheets [2,3]. Free-hanging graphene is the thinnest conceivable object and thus offers many exciting directions for future research. It is a gapless semiconductor with its carriers behaving as massless Dirac fermions exhibiting ballistic transport making, thus, graphene very useful in device applications. A graphene ribbon can be either conducting or semiconducting allowing various nanometer-size structures to be carved to make a single-electron-transistor (SET) circuitry. The advantage is that everything including conducting channels, quantum dots, barriers and interconnects can be cut out from a graphene sheet. This is a tremendous advantage over the current Si-based technology. We propose to perform theoretical investigations of various two and three terminal graphene ribbon junctions to lay the foundation of future generation of cheap to produce molecular electronic devices that are stable at room temperatures and above. In particular, we will perform quantum conductivity calculations and explicitly obtain current vs. voltage (I-V) characteristics for all types of graphene ribbon junctions that can be directly compared with experiments. Our considerable experience with such calculations for carbon nanotube junctions will come in handy. The theoretical predictions can be used as guides in the experimental synthesis of these exciting new class of future molecular devices. [1] K. S. Novoselov et aI., Science Vol. 306,666 (2004). [2] J. C. Meyer et al. •• Nature, Vol. 446,60 (2007). [3] S. V. Morozov et aI., Phys. Rev. Lett., Vol. 97, 016801 (2006).